Electromagnetic relay having removable contact and coil assemblies



1965 J. R. BURCH ETAL 3,198,910

ELECTROMAGNETIC RELAY HAVING REMOVABLE CONTACT AND COIL ASSEMBLIES Filed July 11, 1962 2 Sheets-Sheet 1 F/G.2. 27 2o 27 2f 2; 2s 20' 2s 26 a0 6 26 26 2s .90 26 2.9 26

//v\/E/\/7'0Rs: JAMES R BURCH, xQ/CHARO L. CHACE,

ATTORNEY.

1965 J. R. BURCH ETAL 3,198,910

ELECTROMAGNETIC RELAY HAVING REMOVABLE CONTACT AND COIL ASSEMBLIES Filed July 11, 1962 2 SheetsSheet 2 F/GJ: F766.

/ N VE N TORS JAMAS R BURCH, R/cHA/w CHACE,

BY ATTORNEY.

United States Patent 0 3,198,930 ELECTRUIl IAQENETEC RELAY HAVING REE 16V- ABLE CGNTAT AND Gilli. ASSIEMiBlLlES James R. Burch, Normal, and Richard L. Chace, loomington, lll., assignors to General Electric Company, a

corporation of New York Filed July 11, 1962, der. No. 209,4l15 20 Claims. (6C1. Milk-104) This invention relates to electromagnetic relays and has particular relation to the mounting and arrangement of parts of electromagnetic relays.

Electromagnetic relays generally include a housing which mounts a plurality of fixed contacts and a plurality of movable contacts which are movable relative to the fixed contacts in response to energization of the coil of an electromagnet carried by the housing. In the design of such relays it is very desirable that the fixed and movable contacts be arranged so as to permit rapid detachment thereof from the housing and also to permit observation of the condition of the contacts. It is further desirable that operating parts of the relay, such as the electromagnet and the fixed and movable contacts, be mounted by the housing in a manner allowing the rapid installation and removal of such parts relative to the housing. Additionally, the fixed contacts and the coil terminals should be located at accessible areas to facilitate wiring operations.

In certain previous relay designs the housing supports the electromagnet, including a coil and a magnetic core for the coil, in such a manner that in order to remove the coil and core from the housing it is necessary to dismantle the housing and to also remove the fixed contacts from the housing. Such disassembly operation is quite bothersome and time consuming and can also result in loss of the dismantled parts. It is very advantageous to provide a relay having parts arranged in a manner such that the electromagnet can be readily installed and removed with respect to the housing Without disturbing the housing and without detaching the fixed contacts from the housing.

A further desirable feature in relays of this type is the provision of an arrangement for mounting the fixed and movable contacts so that these contacts can be quickly converted between normally open and normally closed conditions, and so that the movable contacts wipe across the fixed contacts when moved into engagement therewith.

While numerous relay designs have heretofore been proposed, these designs have either failed to incorporate one or more of the above desirable features or have been of bulky multi-part construction resulting in a comparatively expensive device.

It is therefore a primary object of the present invention to provide a novel and improved electromagnetic relay of low cost having a minimum number of parts which are compactly arranged in a manner permitting rapid assembly and disassembly thereof relative to one another.

It is another important object of the invention to provide an electromagnetic relay including a split housing mounting a plurality of fixed and movable contacts and an electromagnetic actuator for moving the movable contacts relative to the fixed contacts with the parts so mounted and arranged that the electromagnet can be installed and removed relative to the housing without disturbing either the housing or the fixed contacts thereon.

It is a further object of the invention to provide an electromagnetic relay having a novel and improved arrangement oi fixed and movable contacts permitting rapid conversion of the contacts between normally open and normally closed conditions.

It is still another object of the invention to provide a ice novel and improved electromagnetic relay having fixed and movable contacts which are exposed to permit observation of the condition of such contacts and to facilitate wiring of the fixed contacts.

It is a still further object of the invention to provide an electromagnetic relay having a novel and improved movable contact carrier arranged to releasably mount a plurality of bridging contacts in a manner permitting the rapid installation and removal of the contacts relative to the carrier and permitting the repositioning of the contacts to convert between normally open and normally closed contact conditions.

it is still another object of the invention to provide an electromagnetic relay having fixed contacts and a movable contact carrier mounting a plurality of bridging contacts in a unique manner which provides a positive wipin g action between the fixed and movable contacts.

In carrying out the invention in one preferred form an electromagnetic relay is provided including a split housing including identical detachably connected housing halves defining when connected a central cavity which houses the electromagnet and armature assembly and which has an open end of cross-shaped configuration opening at the top of the housing. A plurality of fixed contacts are mounted at the top of the housing in spaced exposed parallel rows which are spaced from the open end of the cavity.

The electromagnet includes a coil assembly and a magnetic core extending through the coil assembly and has a generally cross-shaped cross section conforming substantially to the configuration of the cross-shaped open end of the cavity. The arrangement is such that the coil and core can be installed and removed relative to the cavity as a unit by movement thereof through the cross-shaped open end without disassembling the housing and without detaching the fixed contacts from the housing. The coil includes terminals connected thereto which are located in the two rows of fixed contacts when the electromagnet is installed within the housing.

The magnetic armature assembly includes a projection extending through the open end of the cavity into a groove formed in the bottom of a contact carrier which is releasably mounted in the space between the rows of fixed contacts and which overlies a part of the open end of the cavity. The contact carrier mounts a plurality of bridging contacts so as to impart thereto a component of movement relative to the carrier which is transverse to the direction of carrier movement to provide a wiping action of the bridging contacts on the fixed contacts when the contacts engage. The fixed and movable contacts are detachably mounted respectively by the housing and by the carrier so as to be readily removed therefrom and repositioned to eiiect conversion of the contacts from normally open to normally closed conditions. A resilient channel-shaped carrier retainer is detachably mounted in snap-in-engagement with the housing to retain the carrier in operative position.

Other objects and advantages of the invention will become apparent from the following description taken in coniunction with the accompanying drawings in which:

FIG. 1 is a view in top plan of the relay of the present invention;

FIG. 2 is a view similar to FIG. 1 but with the movable contact carrier and the carrier retainer removed;

-3. 3 is a view in side elevation of the relay of FIGS. 1 and 2;

FIG. 4- is a view in side elevation of the interior of onehalf of the housing with the fixed contacts removed therefrom;

FIG. 5 is a view in section taken along the line 5-5 of PEG. 1;

FIG. 6 is a view in section taken along the lines 65 of FIG. 1;

FIG. 7 is a view in top plan showing the contact carrier with the cover thereof swung open; and

FIG. 8 is a fragmentary View showing the manner of connecting two adjacent movable contact carriers for movement as a unit.

Referring now to the drawings there is illustrated in FIGS. 1 and 2 an electromagnetic relay represented generally by the numeral 11 embodying the present invention. The particular relay illustrated is designed to have a 300 volt, l ampere rating and in general includes a split insulating housing 11 detachably mounting a plurality of fixed electro-conductive contacts 12 and 13 in two spaced parallel exposed rows at the top face of the housing. The housing 11 also releasably mounts a reciprocable contact carrier 14 in the space between the two rows of fixed contacts. The carrier 14 detachably supports a plurality of bridging contacts 15 and is mounted for reciprocation to move the contacts 15 relative to the contacts 12 and 13 in response to movement of a magnetic armature assembly 16 within the housing resulting from energization of an electromagnet 17 also within the housing.

More specifically, the housing 11 is comprised of two identically configurated housing halves 13 and 19 which are secured together by suitable fastening means 20 to form a central cavity 21 opening at the top face 22 of the housing. The cavity 21 is configurated to contain the magnetic armature assembly 16 and the electromagnet assembly 17 including a coil 23 and a core 24 extending through the coil as will be described more fully hereinafter.

In order to accommodate the fixed contacts 12 and 13 the housing parts 18 and 19 include respectively sets of insulating barriers 25 and 26 upstanding from the top faces thereof with the barriers of each set spaced along the length of the associated housing part. The barriers 25 on the housing part 18 form a plurality of contactreceiving compartments 27 and an intermediate coil terminal-receiving compartment 28 (FIGS. 1, 2 and 4), and in a similar manner the barriers 26 on the housing part 19 form a plurality of contact-receiving compartments 29 and a central coil terminal-receiving compartment 39 (FIGS. 1, 2 and 3). In the illustrated embodiment each housing part has four contactreceiving compartments to provide a four-pole relay. The coil terminal-receiving compartments 28 and 30 are oppositely disposed and communicate with the cavity 21 when the housing parts are connected in order to receive terminals connected to the coil 23 as will be described more fully hereinafter. Each of the compartments 27-30 is open at its ends and at its top so that the fixed contacts 12 and 13 and the coil terminals are completely accessible for wiring operations.

When the housing parts 18 and 19 are connected, the compartments 27 and 23 on the part 18 and the compartments 29 and 30 on the part 19 are disposed in two parallel spaced rows on opposite sides of the plane of separation of the housing parts 18 and 19 which passes through the central longitudinal axis of the device as shown in FIG. 2. The compartments 27 and 29, which receive the contacts 12 and 13, are spaced above and laterally from the open end 33 of the cavity. The open end 33 is of generally cross-shape configuration as viewed from the top of the housing (FIG. 2) and is defined by slot portions 34 and 35 disposed at right angles to each other, the portion 34 of the open end being beneath a recess 36 which is defined by the inner ends of the several barriers 25 and 26 and which opens at the ends of the housing, and the portion 35 of the open end 33 extending perpendicular to the two rows of compartments beneath the coil terminal-receiving compartments 28 and 30. As will appear hereinafter, the coil 23 and the core 24, forming the electromagnet 17, are installed and removed as a unit relative to the cavity 21 by movement thereof through the cross-shaped open end 33 of the cavity 21.

The cavity 21 is formed by recesses 38 in the inner walls of the housing parts 18 and 1) which are in communication when the housing parts are connected. FIG. 4 shows the recess 3% of the housing part 13.

In accord with the present invention the fixed contacts 12 and 13 are mounted within the compartments 27 and 29 so as to be installed and removed relative to the coinpartrnents by movement of the fixed contacts in directions extending generally parallel to the direction of spacing of the two compartment rows. For this purpose each of the contact-receiving compartments 27 and 29 includes a pair of oppositely facing spaced contact-supporting shelves 4t) and 41 (FIGS. 1 and 4) projecting towards each other from the inner walls of the adjacent barriers. As shown in FIG. 6 each of the contacts 12 and 13 includes a generally U-shaped contact tip support 42 having parallel resilient legs 43 connected by a base 44 with the legs 43 straddling the shelves 4-9 and 41 and extending toward the recess 36. A terminal screw 45 passes through openings in the legs 43 and in a terminal clamp 46 and extends between the associated shelves and 41, the clamp 46 being positioned between the head of the screw and the upper one of the legs 43 so that when the screw 45 is loose, the end of an electric conductor (not shown) can be inserted in the space between the upper one of the legs 43 and the clamp 46 each of which has an upwardly curved end to facilitate the insertion of wires. Tightening of the screw 45 securely clamps an inserted conductor (not shown) in position and also effects tight engagement between the legs 43 and the shelves at) and 41 preventing accidental detachment of the contacts 12 and 13 from its compartment. The contacts are readily removed from their compartments by merely loosening the screws 45 to disengage the legs 43 and the shelves 49 and 41 and to release the inserted wires (not shown). The contacts may then be slid out of their compartments in directions away from the recess in by the application of a force to the inner ends of the contacts.

The contacts 12 and 13 include respectively contact tips 50 and 51 which are supported by the respective supports 42 in diiferent orientations so that when two contacts 12 and 13 are positioned in oppositely facing one of the compartments 27 and 29 the tips 51) and 51 thereof are in a common plane and face in a common direction. For this purpose the tip 51 of each contact 12 is supported on an arm 52 which extends from the upper leg 43 of the support 42 towards the recess 36 and which is offset to one side of the contact center. in contrast to this arrangement the tip 51 of each contact 13 is supported on an arm 53 which projects from the upper leg 43 of the support 42 toward the recess 36 and which is offset to the other side of the contact center. In FIG. 2, the arm 52 of the contact 12 in the upper left compartment 27 is offset to the left of the contact center with the tip 50 facing towards the right whereas the arm 53 of the contact 13 in the next adjacent compartment 27 is offset to the right of the contact center with the tip 51 facing towards the left. It is thus seen that the contact tips 50 and 51 of the contacts 12 and 13 can be selectively positioned in a common plane facing in one direction or the other by merely interchanging the contacts 12 and 13 between oppositely disposed compartments 27 and 29 inthe two contact rows. This arrangement permits conversion of the contacts between normally open and nor-- mally closed conditions. When the contacts 12 and 13 are inserted in their compartments, lower parts of the arms 52 and 53 are received in appropriate ones of a plurality of slots 55 formed in the bases of the compartments to properly locate the contacts.

In order to effect connection and disconnection of the contacts 12 and 13 in oppositely disposed compartments of the two contact rows there is provided the contact carrier 14 which supports the bridging contacts 15 and which is releasably mounted within the recess 36 for reciprocation in the direction of extension of the fixed contact rows relative to the fixed contacts. The carrier 1 is supported by longitudinally spaced ledges 66 and adjacent the ends of the recess 36. As best shown in FIG. 7 the carrier 14 includes a base 62 which detachably supports the bridging contacts 15 and a cover 63 which is mounted by the base 62 for pivotal movement with respect thereto through approximately ninety degrees between a first closed position wherein the cover 63 overlies the base 62 and a second open position wherein the cover 63 extends perpendicular to the base 62 and exposes the contacts 15 to permit installation and removal thereof. The cover 63 is illustrated in FIG. 7 in its open position to expose the contacts 15.

In order to detachably support the bridging contacts 15 the base 62 of the carrier 14:- includes a plurality of upstanding longitudinally spaced insulating barriers comprised of alternately disposed tall barriers 64 and alter nately disposed short barriers 65 intermediate the barriers 64. The barriers 64 define a plurality of compartments 66 there being four such compartments shown in the illustrated embodiment. Each compartment contains a barrier 65 at its approximate center and each barrier 65 has an opening 68 with parallel side walls 69 inclined at an angle to the longitudinal axis of the base 62. The barriers 65 at the ends of the carrier 14 have inwardly disposed inclined faces 70 which are generally perpendicular to the planes defined by the side walls 69 of the adjacent barriers 65. The three remaining barriers 64 each has two opposing parallel faces 71 and '72 which are at right angles to the side walls so of the adjacent barriers 65. It is noted that the faces 70, 71 and 72 of the barriers 64- are in confronting relation through the openings 68 of the adjacent barriers 65.

The bridging contacts 15 are designed for positioning each within a separate one of the compartments 66 and the arrangement is such that each bridging contact can be positioned within its compartment in two diiferent orientations to define with the associated fixed contacts normally open or normally closed contact conditions respectively as desired. For this purpose each contact 15 is of substantially identical configuration and includes a tip support 75 having a generally U-shaped intermediate section with spaced parallel legs 76 connected by a base 77. Connected to the legs 76 are a pair of laterally extending arms 78 located in a common plane inclined at an angle to the planes of the legs 76. The arms 7 carry contact tips 79 located on the sides of the arms adjacent the U-shaped section. When the contacts 15 are installed in their respective compartments as, the legs 76 of each contact are between and in contact with the side walls 79 of the associated barrier 65 with the base 77 in engagement with one of the inclined faces 7%, 71 or 72. Each contact 15 includes a coil spring d which is attached to the inner face of the base 77 and which has a free end engaging the other of the inclined faces 70, 71 or 72.

The left-hand one of the contacts 15 is viewed in FIGS. 1 and 7 is shown in FIG. 1 engaging two fixed contacts 12 and 13 in its normally closed condition, and is shown in FIG. 7 with its base 77 engaging the face 70 of the left end barrier 64-, with its spring 80 engaging the face 71 of the adjacent barrier 64, and with its tips 79 facing towards the left so as to engage the tips and 51 of the left-hand contacts 12 and 13 (FIG. 1). The lefthand contact is readily convertible to a normally open condition by removing the contact from its compartment, rotating the contact end for end and replacing the contact in its compartment. The contact 15 in the second compartment from the left is shown in such normally open condition. At the same time, the left-hand fixed contacts 12 and 13 are interchanged to assume the positions of the adjacent set of contacts 12 and 13.

The described arrangement for mounting the contacts all) 15 provides a very effective wiping action between the contacts 15 and the fixed contacts 12 and 13. Initial movement of the carrier 14 toward the right as viewed in FIG. 1 causes a normally open contact 15 to engage the associated fixed contacts, and continued movement of the carrier causes the spring to compress which results in movement of the contact 15 relative to the fixed contacts in a transverse direction relative to the axis of the carrier due to the cooperation between the side walls of the associated barrier 65 and the inclined legs 76 of the contact.

The contact carrier includes the cover 63 which is mounted on the central one of the barriers 64 for pivotal movement relative to the base 62 about an axis perpendicular to the longitudinal axis of the base. The cover 63 has on its lower surface a cylindrical projection 83 positioned within a cylindrical recess 84 formed on the upper surface of the central barrier 64. The projection 83 and recess 84 include aligned openings for receiving a screw 85 which threadably engages a nut 86 positioned in a recess 87 on the upper surface of the cover 82. The cover includes longitudinally-spaced transversely extending slots 88 in its lower surface which receive the two taller ones of the barriers 64 when the cover is pivoted in a clockwise closing direction from the open position shown. The end ones of the barriers 84 include upstanding projections 90 which engage shoulders 91 formed on the ends of the cover 82 to limit pivotal movement of the cover in the closing direction. A projection 92 extends from the left-hand end of the base to engage a recess 93 formed at the left-hand end of the lower surface of the cover to provide a detenting action which prevents accidental opening of the cover.

In order to effect reciprocation of the carrier 14 electromagnetic actuating means is provided within the cavity 21 of the housing and includes the armature assembly 16 and the electromagnet 17 (FIGS. 5 and 6). The electromagnet 17 is comprised of the coil 23 which includes electroconductive wire wound on a coil form having a central opening 101 which receives the generally rectangular magnetic core 24. The coil form 100 has at its top a pair of laterally extending projections 101 to the upper surfaces of which are secured generally U-shaped terminal arms 102 to which the ends of the wire of the coil are attached. Terminal clamps 103 having upwardly curved ends are secured to the upper parts of the arms 102 by screws 104 which extend through aligned openings of the terminal clamps and arms. The core 24 includes a tab 105 struck from its upper surface which engages the end of one of the projections 101 to position the core symmetrically relative to the coil 23.

The electromagnet consisting of the coil 23 and core 24 is of generally cross-shaped cross section taken in a plane perpendicular to the coil and passing through the coil and core. This cross section is dimensioned to conform generally to the cross-shaped open end 33 of the housing cavity 21 so that the assembled electromagnet can be readily installed and removed relative to the cavity 21 by movement thereof through the open end of the cavity 21 without disturbing the housing and the fixed contacts mounted thereon. The inner walls of the housing parts 18 and 19 are formed with opposed vertically extending slots 110, the slot of the housing part 18 being shown in FIG. 4, which receive the ends of the core 24 to guide the electromagnet into operative position within the cavity. The slots 110 terminate short of the base of the cavity 21 to provide ledges 111 which support the core and thereby the electromagnet above the base of the cavity and substantially in the center thereof.

When the electromagnet is operatively positioned within the cavity 21, the terminal arms 102 attached to the coil form 100 project upwardly from the cavity 21 so that the terminal clamps 103 are positioned within the opposed compartments 28 and 30 substantially in alignment with the terminal clamps 46 in the compartments 27 and 29.

To firmly and releasably maintain the electromagnet within the housing there is provided a generally flat spring plate 112 (FIG. mounted by the housing within the cavity 21 at the right hand side thereof as viewed in FIG. 2. The plate 112 is supported by means of opposed slots 113 in the housing parts which receive the ends of the plate 112, the slot 113 of the housing part 18 being shown in FIG. 4, and the plate 112 includes an upper inwardly bowed projection 114 which is deflected by the coil form when the electromagnet is installed and which engages the coil form under tension to firmly maintain the electromagnet in operative position. The electromagnet is readily removed from the cavity 21 by merely loosening the screws 104 to release the inserted wires (not shown), grasping the screws 104, and lifting the electromagnet out of the cavity through the open end thereof. To install the electromagnet it is only necessary to plug it into the cavity through the open end thereof without any further operations.

The armature assembly 16 includes a generally U-shaped magnetic armature 120 having spaced parallel legs 121 which are connected by a base 122 and which straddle and are secured to one arm 123 of a generally L-shaped bracket 124. The bracket includes an additional arm 125 which is generally perpendicular to arm 123 and which extends along the base of the cavity beneath the electromagnet. The arm 125 carries laterally extending aligned cylindrical projections 126 loosely received in opposed circular openings 127 formed in the two housing parts to pivotally mount the bracket and the armature for movement about an axis parallel to the direction of spacing .of the two rows of fixed contacts. The opening 127 of the housing part 18 is shown in FIG. 4. The legs 121 of the armature are located on the left hand side of the core 24 as viewed in FIG. 5 and straddle a portion of the coil form 100 so that the end faces of the legs 121 are adjacent the left hand side of the core 24. The armature .is normally biased away from the core 24 by a coil spring 130 positioned on the right hand side of the core 24 and in engagement with the lower surface of the arm 125 and the base of the cavity 21.

In order to operatively and releasably connect the armature assembly 16 and the contact carrier 14, the arm 123 of the bracket 124 includes an upwardly extending projection or tab 131 (FIGS. 2 and 5) which is normally urged against the left hand end Wall of the cavity and which loosely fits within a notch 132 (FIG. 5) formed in the bottom wall of the base 62 of the contact carrier.

When the coil 23 is energized, the armature 120 is magnetized and the armature assembly is pivoted in a clockwise direction as viewed in FIG. 5 against the bias of spring 130 so that the projection 131 effects movement of the contact carrier toward the right relative to the fixed contacts. When the coil 23 is deenergized, the armature 12% returns to its normal illustrated position by expansion of the previously compressed spring 130 to .return the contact carrier to its normal position.

In order to retain the contact carrier 14 in operative position relative to the housing, there is provided a channel-shaped resilient retainer 135 having lower laterally-extending flanges 136 at its ends received within slots 137 formed in the confronting faces of the end ones of the barriers 25 and 26. The slots 137 of the housing part 18 are shown in FIG. 4. An elongated opening 138 is formed in the base of the retainer 135 to receive a projection 14% extending from the upper surface of the cover 63 of the contact carrier. Thus, the relay may be actuated manually by merely grasping the projection 14% and reciprocating the carrier. Indicia in the form of the words ON and OFF are provided on the base of the retainer to indicate the condition of energization of the electromagnet. To permit removal of the electromagnet from the cavity it is only necessary to remove the retainer 135 from the housing and to lift out the contact carrier 14.

While a four poie rclay is shown in the drawings, the

number of poles may be conveniently increased, and for this purpose the contact carrier 14 may be readily connected as shown in FIG. 8 to a similar contact carrier 141 of an auxiliary contact device 142 having fixed contacts but having no electromagnetic actuating means. To this end the lower surface of the base 62 of the contact carrier 14 is provided with enlarged circular openings 143 which open at the ends of the base 62 through slots 144 formed in the end walls thereof. Similar slots and openings may be formed in the contact carrier 141 to receive enlarged circular terminals 145 of a connecting piece 146 which serves to connect the carriers 14 and 141 for movement as a unit in response to energization of the coil 23.

The relay may be mounted on a panel 159 (FIG. 3) or other supporting surface by mounting screws 151 held captive in vertically extending recesses 152 formed adjacent the corners of the relay.

As previously stated the housing parts 18 and 19 are of substantially identical configuration and in addition, each housing part is symmetrical about a central vertical plane as viewed in FIG. 4. Thus, each housing part includes two slots 113 and two openings 127 which permits any two housing parts to be used interchangeably on either side of the device.

While we have shown and described a particular embodiment of our invention, it will be obvious to those skilled in the art that various changes and modifications may be made without departing from our invention in its broader aspects and we, therefore, intend in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An electromagnetic relay comprising, an insulating housing including two substantially identical detachably connected housing parts configured to form when connected a central cavity having an open end opening at a side of the housing, fixed contacts mounted on said housing parts and disposed in two parallel space-d exposed rows on each side of the open end of the cavity when the housing parts are connected, each housing part carrying a separate one of said contact rows, a contact carrier removably mounted by said housing between said spaced rows and overlying the open end of said cavity for reciprocation relative to the fixed contacts, said housing parts being separable along a plane which passes through the approximate center line of said carrier and which is perpendicular to the direction of spacing of said rows of fixed contacts, a coil assembly including a coil supported within said cavity, spaced .terminals connected to said coil and positioned externally of the cavity with each terminal in a separate one of said rows of fixed contacts, and a magnetic armature assembly mounted within said cavity for pivotal movement relative to the housing and releasably connected to said carrier to eiiect reciprocation thereof in response to energization and deenergization of said coil.

2. An electromagnetic relay comprising, an insulating housing having a cavity with a restricted open end opening at a side of the housing, a plurality of fixed contacts mounted on said housing side clear of the open end of the cavity and arranged in two parallel spaced exposed rows on opposite sides of said open end, said open end having a predetermined width dimension extending parallel to the direction of spacing of said rows, a contact carrier removably mounted between said spaced rows for reciprocation relative to said fixed contacts, a plurality of bridging contact-s carried by the carrier in spaced relation along its length for cooperation with said fixed contacts, a coil releasably supported within said cavity and having a predetermined thickness dimension in alignment with and extending parallel to the width dimension of said open end, and a magnetic armature assembly mounted within the cavity for movement relative to the housing and releasably connected to said carrier to efiect reciprocation thereof in response to energization and dcenergization of the coil, the thickness dimension of said coil being less than the width dimension of said open end so that the coil can be installed and removed relative to the housing by movement thereof into and out of said cavity through the open end without disturbing said fixed contacts and said housing when said carrier is removed from the housing.

3. An electromagnetic relay comprising, an insulating housing having a cavity with an open end opening at a side of .the housing, a plurality of fixed contacts mounted on said housing side in two parallel spaced exposed rows, a cont act carrier removably mounted between said spaced rows and overlying the open end of said cavity for reciprocation relative to the fixed contacts, a plurality of bridging contacts carried by the carrier in spaced relation along its length for cooperation with said fixed contacts, a coil assembly including a coil within the cavity and having an opening, a magnetic bar extending through said coil opening and having ends on opposite sides of said coil, a magnetic armature assembly within said cavity releasably connected to said contact carrier, said armature assembly including a U-shaped armature having legs straddling said coil on one side of said bar, and a pivotaily mounted bracket supporting the armature and having a base extending beneath the coil .to the other side of said bar; and resilient means engaging the housing and the base at said other side of the bar to bias the armature legs away from said bar.

4. A relay as defined in claim 3 wherein said coil and said bar are installed and removed as a unit relative to the housing by movement thereof into and out of said cavity through the open end of said cavity without disturbing said fixed cont-acts and said housing when said carrier is removed from the housing.

5. An electromagnetic relay comprising, an insulating housing having a cavity with a cross-shaped open end opening at a side of the housing, a plurality of fixed contacts mounted on said housing side in two parallel spaced exposed rows which are on opposite sides of one part of said open end and which extend generally perpendicular to the other part of said open end, a contact carrier removably mounted between said rows and overlying said one part of said open end for reciprocation relative to said fixed contacts, a plurality of bridging contact-s carried by the carrier for cooperation with said fixed contacts, an electromagnet including a coil and a magnetic core for the coil releasably mounted within said cavity, said electromagnet having a cross-shaped cross section dimensioned to permit installation and removal thereof 'elative to the housing by movement thereof into and out of said cavity through said cross-shaped open end without disturbing said fixed contacts and said housing when said carrier is removed from said housing, and a magnetic armature relcasably connected to said carrier and mounted within said cavity for movement relative to the housing in response to energization and deenergization of said coil.

6. A relay as defined in claim 5 wherein said other part of said open end interrupts said rows of fixed contacts, said coil having spaced terminal arms extending through said other part of said open end and including terminals in said rows of fixed contacts.

'7. An electromagnetic relay comprising, an insulating housing, a plurality of fixed contacts mounted by the housing at exposed areas in two parallel spaced rows, a contact carrier mounted between said rows of fixed contacts for straight line reciprocation relative to the fixed contacts, a plurality of bridging contacts mounted by the carrier in spaced relation along its length for cooperation with the fixed contacts, and means mounted by the housing energizable to effect reciprocation of said contact carrier, said contact carrier including a base having slots ii therein for releasably mounting said bridging contacts, and a cover mounted on said base for pivotal movement relative to the base between a first position wherein the cover overlies the bridging contacts in the base and a second position wherein the cover exposes the bridging contacts for release thereof from the base.

8. A relay as defined in claim 7 wherein said bridging cont acts and said base have cooperating surfaces inclined at an angle to the direction of reciprocation of the carrier permitting movement of said bridging contacts relative to the carrier at said angle.

9. An electromagnetic relay comprising, an insulating housing having a cavity with a cross-shaped open end opening at a side of the housing, a plurality of spaced upstanding barriers on said housing side defining contactreceiving compartments arranged in two parallel spaced rows on opposite sides of one part of said open end, the space between the rows of compartments communicating with said cavity through said one part of said cross-shaped open end, said rows of compartments containing two opposed compartments communicating with said cavity through. the other part of said cross-shaped open end, a plurality of fixed contacts detachably mounted in said compartments, a contact carrier removably mounted in the space between said rows of compartments for reciprocation relative to the fixed contacts, a plunality of bridging contacts mounted by the carrier in spaced relation along its length for cooperation with said fixed contacts, an electromagnet within said cavity including a coil and a magnetic core passing through the coil, said coil and core having a cross-shaped cross section dimensioned so that the coil and core can be installed and removed relative to the housing as a unit by movement of the coil and core into and out of said cavity through said open end without disturbing said fixed contacts and said hous ing when said carrier is removed from said housing, terminals connected to said coil positioned within said opposed compartments when the coil and core are assembled relative to the housing, and a magnetic armature mounted within the cavity for movement relative to the core in response to energization of said coil, s aid armature including a part extending into releasable engagement with said contact carrier for reciprocating the carrier in response to movement thereof.

Zlti. An electromagnetic relay comprising, an insulating housing, a plurality of fixed contacts mounted on a side of the housing in two parallel spaced rows, a contact carrier mounted by the housing in the space between said rows of fixed contacts for reciprocation relative to the fix-ed contacts, said contact carrier including a plurality of upstanding barriers spaced in the direction of reciprocation of said carrier, alternate first ones of said barriers each havirn an opening with a pair of parallel side walls inclined at an angle to the direction of spacing of said barriers, said barriers defining a plurality of pairs of compartments with the compartments of each pair being defined by alternate second ones of said barriers and communicating through the opening of the associated intermediate first barrier, said second barriers having inclined panallel faces which confront each other through the opening of the associated intermediate first barrier and which extend at substantially right angles to the side walls of the opening of the associated intermediate first barrier, and a plurality of bridging contacts each within one compartment of a separate pair of compartments for cooperation with said fixed contact-s, each bridging contact having a pair of contact tips on opposite sides of said car ier in a common plane and having an inclined U- shaped portion displaced from said common plane, said U-sha-ped portion having legs engaging respectively the inclined Walls of the opening in the associated first barrier and having a base engaging the inclined face of one associated second barrier, and a coil spring having ends engaging respectively said U-shaped portion and the inclined face of the other associated second barrier.

11. A relay as defined in claim it) wherein said carrier includes a base having said barriers upstanding therefrom, and a cover mounted on the base for pivotal movement relative to the base about an axis generally perpendicular to the longitudinal axis of the base.

12. An electromagnetic relay comprising, an insulating housing including two substantially identical detachably connected housing parts configured to form when connected a central cavity having an open end opening at a side of the housing, fixed contacts mounted on said housing parts and disposed in two panallel spaced exposed rows on each side of the open end of the cavity when the housing parts are connected, each housing part carrying a separate one of said contact rows, a contact carrier removably mounted by said housing between said spaced rows and overlying the open end of said cavity for reciprocation relative to the fixed contacts, said housing parts being separable along a plane which passes through the approximate center line of said carrier and which is perpendicular to the direction of spacing of said rows of fixed contacts, a coil assembly including a coil supported within said cavity, spaced terminals connected to said coil and positioned externally of the cavity with each terminal in a separate one of said rows of fixed contacts, and a magnetic armature assembly mounted within said cavity for pivotal movement relative to the housing and releasably connected to said carrier to cited reciprocation thereof in response to energization and deenergization of said coil, said housing parts defining a pair of spaced end walls each having a separate recess communicating with the space between said rows of fixed contacts, said carrier having ends exposed through said recesses and adapted for connection to an auxiliary contact carrier.

13. An electromagnetic relay comprising, an insulating housing, a plurality of spaced upstanding barriers on a side of the housing defining contact receiving compartments arranged in two parallel spaced rows, a plurality of fixed contacts detachably mounted in said compartments, a contact carrier removably mounted in the space between said rows of compartments for reciprocation relative to the fixed contacts in directions substantially parallel to said rows of compartments, a plurality of bridging contacts mounted by the carrier in spaced relation along its length for cooperation with said fixed contacts, opposed ones of said compartments having confronting open sides which are substantially closed by sair carrier, each bridging contact having a pair of ends each extending into a separate one of said compartments for cooperation with the fixed contacts in said compartments, said bridging contacts and said fixed contacts residing in parallel planes which are parallel to said upstanding barriers, an electromagnet mounted by the housing including a coil, and a magnetic armature mounted for movement relative to the coil in response to energization of said coil, said armature being releasably connected to said carrier for reciprocating the carrier in response to energization of said coil, and a cover in detachable engagement with said housing and overlying said carrier, said cover being positioned clear of said contact compartments so that said bridging contacts and cooperating fixed contacts are exposed tor unobstructed observation.

14. An electromagnetic relay comprising, an insulating housing having a cavity with a cross-shaped open end opening at a side of the housing, a plurality of spaced upstanding barriers on said housing side defining contact receiving compartments arranged in two parallel spaced rows on opposite sides of one part of said open end, said rows of compartments containing two opposed compartments communicating with said cavity through the other part of said open end, a plurality of fixed contacts detachably mounted in said compartments, a contact carrier removably mounted in the space between said rows of compartments and overlying said one part of the open end for reciprocation relative to the fixed contacts, a plurality of bridging contacts mounted by the carrier in spaced relation along its length for cooperation with said fixed contacts, opposed ones of said compartments having confronting open sides which are substantially closed by said carrier, each bridging contact having a pair of ends each extending into a separate one of said compartments for cooperation with the fixed contacts in said compartments, an electromagnet releasably mounted within said cavity including a coil and a magnetic core passing through the coil, said coil and core having a cross-shaped cross section dimensioned so that the coil and core can be installed and removed relative to the housing as a unit by movement of the coil and core into and out of said cavity through said open end without disturbing said fixed contacts and said housing when said carrier is removed from said housing, terminals connected to said coil positioned within said two opposed compartments when the coil and core are assembled relative to the housing, a magnetic armature assembly mounted Within the cavity for movement relative to the core in response to energization of said coil, said armature assembly including a part extending into releasable engagement with said carrier for reciprocating the carrier in response to energization of said coil, and a cover in detachable engagement with said housing and overlying said carrier, said cover being positioned clear of said contact compartment so that said bridging contacts and cooperating fixed contacts are exposed for unobstructed observation.

15. An electromagnetic relay comprising, an insulating housing including a pair of substantially identical housing parts detachably connected to form a central cavity having a cross-shaped open end opening at a side of the housing, a separate plurality of spaced upstanding barriers on each housing part at said housing side and defining contact receiving compartments arranged in two parallel spaced rows on opposite sides of one part of said open end, said rows of compartments containing two opposed compartments communicating with said cavity through the other part of said open end, a plurality of fixed contacts detachably mounted in said compartments, a contact carrier removably mounted in the space between said rows of compartments and overlying said one part of the open end for reciprocation relative to the fixed contacts, a plurality of bridging contacts mounted by the carrier in spaced relation along its length for cooperation with said fixed contacts, opposed ones of said compartments having confronting open sides which are substantially closed by said carrier, each bridging contact having a pair of ends each extending into a separate one of said compartments for cooperation with the fixed contacts in said compartments, an electromagnet releasably mounted within said cavity including a coil underlying said carrier and defining a plane generally parallel to the axis of reciprocation of said carrier, said coil having a central opening extending generally perpendicular to the plane of the coil, a magnetic bar extending through the opening of said coil and having ends on opposite sides of said coil, a pair of terminals connected to said coil positioned within said two opposed compartments when the coil is assembled, a magnetic armature assembly within said cavity including a U-shaped armature having legs straddling said coil on one side of said bar, and a pivotally mounted bracket supporting the armature and having a first portion extending into releasable engagement with said carrier and having a second portion extending beneath the coil to the other side of said bar; resilient means engaging the housing and the second part of said bracket at said other side of the bar to bias the armature legs away from said bar, said coil and core being installed and removed relative to the housing as a unit by movement of the coil and core into and out of said cavity through said open end without disturbing said fixed contacts and said housing when said carrier is removed from aid housing, and a cover in detachable engagement with said housing and overlying said carrier, said cover being clear of said contact compartments so that said bridging contacts and said fixed contacts are exposed for view unobstructed by said cover.

16. An electromagnetic relay comprising, an insulating housing including a pair of substantially identical housing parts detachably connected to form a central cavity having a cross-shaped open end opening at a side of the housing, a separate plurality of spaced upstanding barriers on each housing part at said housing side and defining contact receiving compartments arranged in two parallel spaced rows on opposite sides of one part of said open end of the housing, said rows of compartments containing two opposed compartments communicating with said cavity through the other part of said open end, a plurality of fixed contacts detachably mounted in said compartments, a contact carrier removably mounted in the space between said rows of compartments and overlying said one part of the open end for reciprocation relative to the fixed contacts, a plurality of bridging contacts mounted by the carrier in spaced relation along its length for cooperation with said fixed contacts, opposed ones of said compartments having confronting open sides which are substantially closed by said carrier, each bridging contact having a pair of ends each extending into a separate one of said compartments for cooperation with the fixed contacts in said compartments, an electromagnet releasably mounted within said cavity including a coil underlying said carrier and defining a plane generally parallel to the axis of reciprocation of said carrier, said coil having a central opening extending generally perpendicular to the plane of the coil, a magnetic bar extending through the opening of said coil and having ends on opposite sides of said coil, a pair of terminals connected to said coil positioned within said two opposed compartments when the coil is assembled, a magnetic armature assembly within said cavity including a Ushaped armature having legs straddling said coil on one side of said bar, and a pivotally mounted bracket supporting the armature and having a first portion extending into releasable engagement with said carrier and having a second portion extending beneath the coil to the other side of said bar; resilient means engaging the housing and the second part of said bracket at said other side of the bar to bias the armature legs away from said bar, said coil and core being installed and removed relative to the housing as a unit by movement of the coil and core into and out of said cavity through said open end without disturbing said fixed contacts and said housing when said carrier is removed from said housing, a cover in detachable engagement with said housing and overlying said carrier, said cover being clear of said contact compartments so that said bridging contacts and said fixed contacts are exposed for view unobstructed by said cover, said cover having a slot overlying said carrier, and an upstanding projection on said carrier extending through the slot of said cover and exposed for manual actuation of said carrier, said housing having spaced end walls each including a separate recess communicating with the space between said compartment rows, said carrier having ends exposed through said recesses and adapted for connection to an auxiliary contact carrier.

17. An electromagnetic relay comprising, an insulating housing having a cavity with an open end opening at a side of the housing, a plurality of fixed contacts mounted on said housing side and arranged in two parallel spaced exposed rows spaced from said open end on opposite sides thereof, a contact carrier removably mounted between said spaced rows for reciprocation relative to the fixed contacts in a direction parallel to the spaced rows, a plurality of bridging contacts carried by the carrier in spaced relation along its length for cooperation with said fixed contacts, the open end of said cavity including a slot communicating with the cavity and extending perpendicular to said spaced rows and interrupting said spaced rows, a coil within said cavity, means including resilient means frictionally and releasably securing said coil within the cavity, a pair of terminals connected to said coil and exidtending through said slot with each terminal disposed in a separate one of said rows, and a magnetic armature assembly mounted within the cavity for movement relative to the housing and releasably connected to said carrier to effect reciprocation thereof in response to energization and deenergization of the coil, said coil and the open end of said cavity being configured such that the coil can be installed and removed relative to the housing by movement thereof into and out of the cavity through the open end of said cavity without disturbing said fixed contacts and said housing when said carrier is removed from the housing.

18. An electromagnetic relay comprising, an insulating housing having a cavity with a cross-shaped open end opening at a side of a housing, said open end having two generally perpendicular parts each having a predetermined width dimension, a plurality of fixed contacts mounted on said housing side in two parallel spaced exposed rows which are on opposite sides of one part of said open end and which extend generally perpendicular to the other part of said open end, said fixed contacts being positioned clear of both parts of said open end, a contact carrier removably mounted between said rows and overlying said one part of said open end for reciprocation relative to said fixed contacts, a plurality of bridging contacts carried by the carrier for cooperation with said fixed contacts, an electromagnet within said cavity and including a coil and a magnetic core for the coil, means including resilient means frictionally and releasably securing said electromagnet within said cavity, said coil underlying said carrier in alignment with said one part of said open end and having a thickness dimension which is less than and which extends parallel to the width dimension of said one part of said open end, said coil having a central opening extending parallel to its thickness dimension, said core extending through the opening of the coil in alignment with said other part of said open end, said core having a thickness dimension which is less than and which extends parallel to the width dimension of said other part of said open end, said coil and core being dimensioned to permit installation and removal therof as a unit relative to the housing into and out of said cavity through said one part and through said other part of said open end respectively when said carrier is removed from said housing, and a magnetic armature releasably connected to said carrier and mounted within said cavity for movement relative to the housing in response to energization and deenergization of said coil.

19. A movable bridging contact carrier for cooperation with a plurality of fixed contacts mounted in a pair of spaced parallel rows on opposite sides of the carrier comprising, an insulating base having an open top, a plurality of upstanding barriers spaced in the direction of reciprocation of said carrier, alternate first ones of said barriers each having an opening with a pair of parallel side walls inclined at an angle to the direction of spacing of said barriers, said barriers defining a plurality of pairs of compartments with the compartments of each pair being defined by alternate second ones of said barriers and communicating through the opening of the associated intermediate first barrier, said second barriers having inclined parallel faces which confront each other through the opening of the associated intermediate first barrier and which extend at substantially right angles to the side walls of the opening of the associated intermediate first barrier, and a plurality of bridging contacts each within one compartment of a separate pair of compartment for cooperation with said fixed contacts, each bridging contact having a pair of contact tips on opposite sides of said carrier in a common plane and having an inclined U-shaped portion displaced from said common plane, said U-shaped portion having legs engaging respectively the inclined side Walls of the opening in the associated first barrier and having a base engaging the inclined face of one associated second barrier, and a coil spring having 15 ends engaging respectively said U-shaped portion and the inclined face of the other associated second barrier.

20. An electromagnetic relay comprising, an insulating housing having an enlarged central cavity with a restricted open end opening at a side of the housing, said open end having a predetermined Width dimension, a plurality of fixed contacts mounted on said housing at said side clear of the open end of the cavity, a contact carrier removably mounted by the housing at said side for reciprocation relative to the fixed contacts, a plurality of contacts carried by the carrier for cooperation with said fixed contacts, a coil within said cavity having a predetermined thickness dimension in alignment with and extending parallel to the width dimension of said open end, means including resilient means frictionally and releasably retaining the coil in said cavity and permitting plugin installation of the coil in the cavity, and a magnetic armature mounted within said cavity for movement relative to said housing and releasably connected to said carrier to effect reciprocation thereof in response to energization and deenergization of said coil, the thickness dimension of said coil being less than the width dimension of said open end so that said coil can be installed and reis moved relative to the housing solely by movement thereof into and out of said cavity through said open end Without disturbing said fixed contacts and said housing when said carrier is removed from said housing.

References Cited by the Examiner UNITED STATES PATENTS 2,064,632 12/36 Schmitt 20087 2,087,895 7/37 Bierenfeld 20087 2,561,450 7/51 Russell 200-104 2,565,467 8/51 Besag et al 200104 X 2,649,521 8/53 Cobb et a1. 20087 2,672,536 3/54 Rosing et a1 20087 2,692,314 10/54 Lawrence 200-104 2,792,469 5/57 Callaway 200-104 2,874,245 2/59 Moyer 200'l04 2,924,685 2/60 Burch 200-466 3,087,031 4/63 Spinelli et al 200104 3,099,730 8/63 Tateishi 200104 BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCI-IAEFER, Examiner. 

2. AN ELECTROMAGNETIC RELAY COMPRISING, AN INSULATING HOUSING HAVING A CAVITY WITH A RESTRICTED OPEN END OPENING AT SIDE OF THE HOUSING, A PLURAOITY OF FIXED CONTACTS MOUNTED ON SAID HOUSING SIDE CLEAR OF THE OPEN END OF THE CAVITY AND ARRANGED IN TWO PARALLEL SPACED EXPOSED ROWS ON OPPOSITE SIDES OF SAID OPEN END, SAID OPEN END HAVING A PREDETERMINED WIDTH DIMENSION EXTENDING PARALLEL TO THE DIRECTION OF SPACING OF SAID ROWS, A CONTACT CARRIER REMOVABLY MOUNTED BETWEEN SAID SPACED ROWS FOR RECIPROCATION RELATIVE TO SAID FIXED CONTACTS, A PLURALITY OF BRIDGING CONTACTS CARRIED BY THE CARRIER IN SPACED RELATION ALONG ITS LENGTH FOR COOPERATION WITH SAID FIXED CONTACTS, A COIL RELEASABLY SUPPORTED WITHIN SAID CAVITY AND HAVING A PREDETERMINED THICKNESS DIMENSION IN ALIGNMENT WITH AND EXTENDING PARALLEL TO THE WIDTH DIMENSION OF SAID OPEN END, AND A MAGNETIC ARMATURE ASSEMBLY MOUNTED WITHIN THE CAVITY FOR MOVEMENT RELATIVE TO THE HOUSING AND RELEASABLY CONNECTED TO SAID CARRIER TO EFFECT RECIPROCATION THEREOF IN RESPONSE TO ENERGIZATION AND DEENERGIZATION OF THE COIL, THE THICKNESS DIMENSION OF SAID COIL BEING LESS THAN THE WIDTH DIMENSION OF SAID OPEN END SO THAT THE COIL CAN BE INSTALLED AND REMOVED RELATIVE TO THE HOUSING BY MOVEMENT THEREOF INTO AND OUT OF SAID CAVITY THROUGH THE OPEN END WITHOUT DISTRIBUTING SAID FIXED CONTACTS AND SAID HOUSING WHEN SAID CARRIER IS REMOVED FROM THE HOUSING. 